In vitro Free Radical Scavenging and Antioxidant Activities of Aqueous Extracts of Crateva adansonii (Three-leaf Plant)

Ethnopharmacological Relevance: Crateva adansonii popularly known as Three-Leaf plant is used in some South Eastern part of Nigeria by traditional medicine practitioners to treat certain diseases such as infertility and infection.

Aim: This research work aimed at investigating the in vitro antioxidant activities of various parts of Crateva adansonii (Three-leaf plant) an Eastern Nigerian medicinal additive using various method of extraction (hot and cold extracts prepared from the root, leaf and stem bark of the plant). This is to know the best method that would give highest antioxidant properties.

Study Design: This work was designed to compare the antioxidant activities of various parts of Crateva adansonii under Ferric thiocyanate (FCT) assay. These include; Hot root extract, cold root extract, hot leaf extract, cold leaf extract, hot stem-bark extract and cold-stem bark extract at various durations. The study was also designed to study the in vitro antioxidative activities, including thiobabituric acid (TBA) assay, diphenyl-β-picryl- hydrazyl (DPPH) radical scavenging effects and reducing power as standard evaluation methods.

Place of Study and Duration of Study: This study took place at the Department of Biochemistry, Faculty of Science, University of Maiduguri, Borno, State Nigeria and the duration of study was eight weeks

Methodology: Parameters were analyzed spectrophotometrically using UV- VIS spectrophotometer (model 725G, China) at room temperature. Hot and cold water were used for the extraction.

Results: It was observed that the antioxidant activities using FTC assay increased as the peroxide concentration decreased with time in all the extracts. The results showed that the hot extracts inhibited lipid peroxidation more than the cold extracts. The hot root extract showed the highest reducing power (p<0.05) among all the other extracts. Hot root extract showed stronger antioxidant activities under FTC assay than cold root extract. Hot leaf extract did not show stronger antioxidant activities than cold leaf extract while hot stem bark extract did not show stronger antioxidant activities than cold stem bark extract. The results were analyzed by one way ANOVA using SPSS statistical soft ware version 16.

Conclusion: The extracts showed a positive DPPH test with the HLE, CRE, and CLE showing strong antioxidant actions respectively. The results demonstrated that the extracts from C. adansonii scavenged free radical, and reduced lipid peroxidation and could serve as a potential source of natural antioxidants. Hot water is therefore better than cold water when doing root extraction of this plant.